The IPTC metadata allows photos to be embedded with details such as the name of the photographer, the date created, location information, the copyright owner and contact details of that person.

Once the watermark and copyright information is added, photos can then be shared and uploaded to sites such as Flickr.

Image courtesy of John D McHugh

The app has been created by John D McHugh, a photojournalist who specialises in working in "challenging environments" around the world. He has worked extensively in Afghanistan, and has also covered the Iraq war, Sudan (Darfur in 2008, and South Kordofan in 2011), and Bahrain during the Arab Spring uprising in 2011.

McHugh told Journalism.co.uk by email: "The rise of social media has coincided with a rise in photography copyright infringement, or theft. Social media encourages sharing, but many people seem to either not understand, or wilfully ignore, photographers' copyright. A simple right click, and save, and a photograph can be taken without permission or licence."

He added: "Marksta's dual approach, visible watermark and IPTC functionality, is designed to offer the greatest possible protection to photographs in the social media age."